This grant is funding clinical studies of: 1) the effect of neuroleptic drugs on serum prolactin levels and blood levels of drugs in relation to clinical response; 2) studies of tricyclic anti-depressants, lithium and monoamine oxidase inhibitors in relation to clinical response; 3) rat studies of the effect of psychotropic drugs, including neurotransmitters, neuromodulators, anti-psychotics, anti-depressants and psychotomimetic drugs on serum prolactin.